[1] The upstream of Cimandiri is located on the Mount Pasir Caringin, Sukamanah village, district of Gegerbitung and discharges into Indian Ocean near Pelabuhan Ratu.

The watershed (Indonesian: Daerah Aliran Sungai/DAS) of Cimandiri has a area of 201,431 hectare, stretching from around Padalarang and the conservation area of Mount Halimun at the upstream to the southwest direction until the river mouth at Pelabuhan Ratu Bay.

[2] DAS Cimandiri comprises also the tributaries of Cimandiri: Cicatih, Cipelang, Citarik, Cibodas, and Cidadap, which flow into Pelabuhan Ratu Bay, Sukabumi Regency.

[2][5][6] Some tributaries of Cimandiri with a length of more than 10 km, from the upstream, are: The river flows in the southwest area of Java with a predominantly tropical monsoon climate (designated as Am in the Köppen-Geiger climate classification).

The warmest month is October when the average temperature is around 26 °C, and the coldest is January, at 18 °C.